160 DESCRIPTION OF SPECIES. 



The leaves preserved flattened on some of the thin sandy shales of Floris- 

 sant very often have the borders erased and the small teeth therefore often 

 destroyed. The medial lobe of the figure has the teeth quite as distinct 

 as in some of the figures of European authors, still more so than in fig. 5 

 of Gaudin, /. c. 



Hab.— Randolph Co., Wyoming. U. S. Geol. Expl. Dr. F. V. Hayden. 



URTICINE^E. 

 ULMACEvE. 



ULMUS, Linn. 



"U. S. Geol. Rep.," vii, p. 1*7. 



Ulmus tenuinervis, Lesqx. 

 Ibid., p. 188, pi. xxvi, figs. 1,3. 



Ul m us Hillise, ep. nov. 



Plale XXVIII, Figs. 1, X 



Leaves narrow, lanceolate-acuminate, very uneqnilateral at base, simply or 

 doubly-serrate; lateral veins curved in passing to the borders, craspedodrouie. 



The leaves are small, 5 to 9 centimeters long, lb to 2 i centimeters 

 broad, short -petioled, thickish ; the base is narrowed on one side in 

 rounding to the petiole, straight on the other ; the teeth of the borders are 

 large, slightly turned up, not very sharp ; the areolation is quite distinct 

 in small irregularly quadrangular meshes, formed by subdivisions of nerv- 

 illes mostly at right angles. 



Hab. — Florissant. Mrs. Hill, who has widely collected and distrib- 

 uted the specimens of fossil plants of that locality. 



Ulmus Br ownel 1 ii , sp. nov. 



Plate XX VIII, Figs. 2, 4. 



Leaves narrow, oblong- lanceolate, unequal at base, simply obtusely dentate; 

 lateral nerves simple, parallel, the lower open; nervilles irregularly branching and 

 anastomosing ; areolation polygonal, loose. 



This species resembles the preceding, differing by the simple teeth 

 and nerves ; the areoles, much larger, formed by irregularly divided 

 nervilles. 



Hab.— Florissant. U. S. Geol. Expl.; White River. W. A. BrownelL 



